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A198189
Primes from the decimal expansion of the golden ratio, phi, sorted first by the final digit index and then by length.
0
61, 3, 3, 1618033, 7, 887, 9887, 39887, 339887, 1618033988749, 89, 8874989, 398874989, 803398874989, 61803398874989, 2, 5, 3, 83, 683, 458683, 3, 43, 5, 3, 563, 6563, 36563, 868343656381, 180339887498948482045868343656381, 11, 811, 58683436563811
OFFSET
1,1
EXAMPLE
For the first two digits, none of 1, 6, and 16 are prime.
The next digit, 1 is not prime, but 61 is, so a(1) = 61. 161 is not prime, so it is not included.
PROG
(PARI) v=[1, 6, 1, 8, 0, 3, 3, 9, 8, 8, 7, 4, 9, 8, 9, 4, 8, 4, 8, 2, 0, 4, 5, 8, 6, 8, 3, 4, 3, 6, 5, 6, 3, 8, 1, 1]
for(n=1, #v, x=0; p=1; forstep(k=n, 1, -1, x+=p*v[k]; p*=10; if(v[k]&&isprime(x), print1(x", "))))
CROSSREFS
Cf. A186205.
Sequence in context: A132096 A051322 A345224 * A102600 A316918 A077331
KEYWORD
nonn,base
AUTHOR
STATUS
approved